The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 27, 2001
Filed:
Dec. 24, 1999
Applicant:
Inventors:
Niels Due Jensen, Bjerringbro, DK;
Pierre Vadstrup, Mundelstrup, DK;
Assignee:
Grundfos A/S, Bjerringbro, DK;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P 5/28 ;
U.S. Cl.
CPC ...
H02P 5/28 ;
Abstract
The method for controlling a voltage/frequency converter controlled single-phase or polyphase electric motor evaluates the phase shifting between the EMF and BEMF by way of the deviation between the zero crossing of the phase current and the voltage produced by the intrinsic induction and readjusts the frequency of the converter accordingly. The measurement of the intrinsic induction is effected in the zero crossing of the current courses of the associated phase, wherein during the measurement the phase is separated from the supply network.